The present invention relates to inflator apparatus for inflating emergency flotation gear such as life rafts and life jackets; and more particularly to an inflator for flotation gear which may be stored at, and operated in, extremely low temperatures.
Liquid CO.sub.2 (carbon dioxide) cartridges have been used for many years as the main source of pressurized gas for inflating various types of inflatable life saving devices such as rafts, vests and jackets. Emergency use of these devices by downed aircrewman has occurred mostly in temperate zones. However, these situations now occur more frequently in the arctic region where temperatures below -20.degree. F. are not uncommon. At these low temperatures, liquid CO.sub.2 changes too slowly to the gaseous phase to provide immediate buoyancy. A rapid change is especially needed in a life raft to enable a downed person in frigid water to board as soon as possible. The longer he or she remains exposed to the cold water awaiting the formation of a boardable raft, the more likely hypothermia will set in. Raft inflation time in excess of five minutes has been observed when CO.sub.2 cartridges were stored in an aircraft at sub-zero temperatures and then activated in water at 32.degree. F. Consequently, lives have been needlessly lost.
In lieu of liquid CO.sub.2 cartridges, solid pyrotechnic inflators have been tried which generate gas from a compacted solid material, but the gas of combustion does not attain the pressure level needed for buoyancy of inflatable gear.